Video imaging is often used to record the three-dimensional (3D) geometry of objects in space. A number of different methods exist, and most make use of images acquired with multiple cameras. For example, the direct linear transformation method is a widely used technique because it is accurate and relatively simple to implement. The direct linear transformation requires images from at least two cameras for 3D reconstruction.
Occasionally, however, the use of multiple cameras is either impractical or too costly. A number of single-camera methods exist, but most record just two-dimensional (2D) geometry. A few single-camera methods for 3D data collection have been described. Each of these single-camera methods imposes the need for something in addition to the camera images. For example, one single-camera 3D application uses a mirror to provide a second view of the object so multi-image techniques could be applied to a single split image. Positioning the mirror is an evident drawback of this approach. This single-camera 3D method is an extension of a multi-camera 3D cinematographic method that applies to objects coupled by joints with known characteristics. This single-camera 3D method is an extension of a multi-camera 3D cinematographic method that applies to objects coupled by joints with known characteristics; however, the extraction is obtained as a least-squares solution to a linear approximation (1st order Taylor series) of complicated non-linear position equations, and is determined iteratively until the solution reaches a specified maximum change between iterations. Another single-camera 3D method uses linkage distances, but assumes parallel camera lines of sight, which is almost never true. Consequently, the reconstruction approximation is only valid in a restricted portion of space.
There is a need in the art to provide an improved system and method for performing three-dimensional imaging using a single camera to reduce equipment cost, to reduce equipment complexity for simpler integration, and to reduce required views of the object.